2001 Seadoo GTX 951 DI water leak after complete rebuild

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Hey guys, so last summer I purchased a 2001 GTX DI and it has been nothing but a headache since. I have owned a few skis prior but never had to do a complete rebuild on one. I am fairly mechanically inclined so when I purchased this ski in need of a rebuild I didn't think much of it, until I did some reading and then the real work started...ha I know some of you must be laughing by now. So after doing plenty of research and reading I made the decision to have all the parts sent out and rebuilt individually and then I would reassemble the engine myself. ( I did this at the time because I wanted the ski for a vacation that we were going on and I had a hard deadline that the shop I was using was unable to make if they did the rebuild...looking back it was the wrong choice but this is where I am now and I am dealing with it...ha) Anyways, I sent the cylinders out and had them re-sleeved to stock bore (professionally by a PWC engine rebuild shop), had the raves sent out as well to make sure they were fit for clearance for the new pistons and I also had the head planed and .002 taken off to get a good flat surface to work with. Along with all of that I purchased a new crankshaft and installed that myself as well. After receiving all the parts back I went to work installing everything according to the manual being sure to torque everything down to spec. After double and triple checking everything it came time to fire the ski, and with the push of a button it was finally running. It started with zero hesitation on the first push of the starter and sounded good running. Within seconds though I was back at rock bottom as I noticed that there was water being pushed out of the head gasket. I immediately shut it off, took the head off, and checked it out, sure enough there was that gray water/oil mixture coating everything, but ONLY in the PTO side cylinder. I called the company that re-sleeved the cylinders to see if maybe they could be leaking around the flange or the exhaust port or maybe they set the PTO side one in too low and they reassured me they did not think that was the problem and that it was probably a bad head gasket. So I overnighted a head gasket and sprayed a thick coat of copper coat on it and reinstalled it to spec the way I had the first time. Once again the ski fired right up and I thought I was in business, the leak was no longer coming from the head gasket and the copper coat had worked, or so I thought. To my disappointment I looked down to instead this time seeing water leaking from around the spark plug on the PTO cylinder, yes that's right guys, it was leaking water right around the spark plug threads!!!

Now I am at a loss and don't really know what the next step for me should be. I have tossed around the idea of taking my cylinders to a machinist and having them deck the jugs to put a flat surface on there and make sure the one cylinder is not lower than the other, but then I may run into psi issues if I take too much off the jugs, remember .002 already came off the head itself. The other thought I had was to just send it to another shop, the whole engine and have them go through it top to bottom and send me back a running motor with a guarantee. Problem I have is that I am very tired of just throwing money at it and not really getting anywhere. Help me out guys, I know there are a few of you that are experts on this particular engine and many of you that are much more knowledgeable than myself, any suggestions, solutions or ideas are welcomed!!!

Thanks in advanced!
I would look to see if water might be spraying form a head bolt, or another hose onto the plug area. The only way it could leak cooling water around the spark plug directly is if the cylinder head is cracked. Lets hope its not that. The head gasket seal relays on the inner bolts to squeeze the outer edge of the water jacket. Any flaws at all & it will leak. I had one leak between the metal layers of the gasket itself, so now I drill out the rivets in the gasket & copper spray all side of the gasket. Did you coat the sealing surface of the head bolts with loctite? There are a lot of potential water leaks on these skis. If you are not seeing the water seep up around the plus, my guess is its spraying from somewhere else & landing around the plug.

How do the plugs look when you pull them back out, they are not wet with water are they?
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When you pull the head (again) you will be able to see if there was a passage leak. The copper coat should leave a nice colored surface to tell.

But, as ragtop said... I'm guessing it's coming from somewhere else. A bad O-ring, or cracked head shell. The cracks are common in cold states. If it wasn't winterized, and the water in the engine freezes... you will crack the head, or the cyl's.
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Sounds like a cracked head. Not common but happens. Buy a used head and another new head gasket since they shouldn't be reused. Make sure both surfaces are clean, decking is not normally necessary. You don't need to use gasket sealant, more trouble than it's worth. A new head gasket will seal fine.

Did you remove the special blue coating from under the bolt heads? I recommend leaving it on if it is in good shape and not torn and then just adding some blue Loctite to it.
Well to adress the first reply the leak is definatly internal, not something leaking onto the head or spark plug hole, it may be in the threds of the plug hole or maybe in the dome. Either way I think we are all thinking the same thing guys, I had suspicion the head may be the culprit with a tiny hairline crack somewhere. I still haven't been able to confirm it for sure but I ended up using a dye and developer on it and will post the picture of what turned out.

I also actually just picked up anot her ski yesterday, a 2000 GTX DI that has a 2000 GTX DI engine and a 2002 GTX DI engine that came with it. Now both motors need rebuild but seeing as how my head on my 2001 951 DI has a questionable leak in the head am I able to use the head off either of those motors in place of mine which may be cracked? I see that one head has 680 in the corner and one has 585 in the corner. My 2001 has 585 in the corner so I'm assuming I can swap those ones but the domes look different than my 2001. I plan on rebuilding both motors becuase I want to get both skis running and then have a spare on the shelf so does it make sense to swap head or to just get a new head for my 2001 engine?

Now my last questions for this post is where do you think the best place to but a used head is? Ebay? Or do you guys have some part guys that you use that might have one kickin around, I checked with my guy and he only has one for a carb 951.

Thanks again for the help guys!

I attached a pic of my head after I used the crack dye and developer, let me know what u guys think.

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